Styx were one of the biggest American rock groups of the '70s, with a string of hit albums and songs including 'Lady,' 'Come Sail Away,' 'Renegade' and 'Blue Collar Man.' The group scored two of their biggest successes with concept albums -- 1977's 'The Grand Illusion,' and 'Paradise Theatre' in 1981. In 1983, Styx released 'Kilroy Was Here,' their most ambitious concept album yet. But within a year, tensions in the group came to a breaking point, bringing the classic era of Styx to an end.

Styx leader Dennis DeYoung felt the only way for the group to top the No. 1 success of 'Paradise Theatre' was to capture the band on film. To that end, he developed an ambitious concept that touched on themes of censorship, totalitarianism and the dangers of increasing technology. 'Kilroy Was Here' would star DeYoung as Robert Orin Charles Kilroy, a rock star imprisoned in a future where rock and roll has been banned.

The story was partially inspired by an incident in which a pair of conservative televangelists had tried to garner publicity by accusing Styx of "backward Satanic masking." The character of the totalitarian dictator Dr. Everett Righteous -- the leader of the fictional Majority for Musical Morality -- was DeYoung's backhanded swipe at Jerry Falwell's Moral Majority.

When DeYoung presented his idea to the group, it met with resistance. Concept albums had been commercially viable in the '70s, but were viewed as passe in the new decade. Kiss had only recently experienced an enormous downturn in their career from a concept album titled 'Music From 'The Elder,'' and Styx guitarists Tommy Shaw and James "JY" Young both feared another concept album after 'Paradise Theatre' would pigeonhole the band.

But as the author of most of Styx' most successful work, DeYoung was in a position to insist, and he went full steam ahead into the project with the rest of the band somewhat reluctantly in tow. The result was a very divisive experience for the group. "I have many times bemoaned the fact that I, through my sheer will, dragged the group into that," DeYoung admitted in an episode of 'Behind the Music.' "It's always best when everyone in the group is on the same page."

DeYoung dominated the record, contributing not only the concept and story, but also both of the hits from the album. 'Mr. Roboto' was the first single, announcing a new direction for Styx right out of the gate. The song's techno-pop sound was not at all to the liking of Shaw or Young, and DeYoung later said it was only meant as a transition from the film into the live 'Kilroy' show. But when the record company did some test marketing, audiences chose 'Mr. Roboto' as the single, and the song shot to No. 3 in the pop charts, creating a new generation of Styx fans -- but also alienating some of the group's existing fans.

DeYoung also brought in 'Don't Let It End,' a melodic pop power ballad in the vein of previous hits like 'Babe' and 'The Best of Times.' Released as the album's second single, it went to No. 6 in the Top 40. DeYoung's 'High Time' was the album's third and final single, which fizzled at No. 48 in the charts.

James Young portrayed Dr. Righteous, and he wrote 'Heavy Metal Poisoning' as a tongue-in-cheek introduction to the character. JY's other contribution was 'Double Life,' a synth-pop track quite unlike the hard-rocking guitarist's usual fare, demonstrating a previously untapped ability to write a pop chorus.

Tommy Shaw struggled with the concept and his portrayal of rock rebel Jonathan Chance, ultimately turning in three songs for the album, but lacking a standout rock track like some of his previous contributions to Styx. The closest he came was 'Cold War,' a pop-rock track that served as a live vehicle for a long guitar solo. His other songs for the album were in a more melodic vein and actually far stronger. 'Just Get Through This Night' was a mid-tempo pop song with an unusual guitar solo and one of Shaw's best-ever vocal performances, while 'Haven't We Been Here Before' was a showcase for a duet between Shaw and DeYoung that A&M Records wanted to release as the album's third single. The label even sprang for an expensive video for the track, but Shaw ultimately refused the song's release.

Despite the group's internal struggles, 'Kilroy Was Here' was a hit upon its release, selling a million copies and reaching No. 3 in the Billboard charts. But the tour in support of the album proved the final straw for Shaw, who was also battling with drugs and alcohol. The live show featured a 10-minute film as the opening act, which then segued into live action in which DeYoung and Shaw acted out the concept's finale live onstage each night, delivering scripted lines in costume as their characters. It was a task for which Shaw had neither any taste, nor any particular ability. He finally snapped on stage at the Capital Centre in Landover, Md., smashing his guitar, throwing the pieces into the audience and storming off stage.

At a hastily convened meeting the next day, Shaw announced he was quitting the band, and shortly after that, the tour wrapped early. Though no formal announcement was made in regard to Styx splitting, DeYoung, Shaw and Young all began working on solo albums. Seven years would pass before Styx would release another studio album -- and then without Shaw, who didn't return to Styx until 1996. Even then, such was Shaw and Young's distaste for the 'Kilroy' album that they steadfastly refused to play any of the music from it.

In an interesting twist of fate, the song that had helped to hasten the end of Styx also revitalized the band's career after 'Mr. Roboto' was featured in a Volkswagen ad in 1998. The track has gone on to become one of the songs most associated with Styx in popular culture, appearing in countless films, television shows, and even being referenced at the Academy Awards. Styx split with DeYoung permanently in 1999, and though the band -- now led by Shaw and Young -- still refuse to play the song live, DeYoung gleefully performs it in all its campy glory at his solo shows.

Watch the 'Kilroy Was Here' Short Film by Styx